Project Overview: We need to develop effective interventions to enhance the efforts of veterans with incomplete spinal cord injury (iSCI) to recover the dynamic balance needed for unrestricted community ambulation. This proposal aims to understand how individuals with iSCI stabilize during maneuvers and to create robotic environments that facilitate practice of either active or passive stabilization of maneuvers. This research will advance our understanding of the impairments that need to be addressed to improve dynamic balance and how to optimize training interventions to effectively improve stability. Investigators: Our leadership team composed of a biomechanist, engineer, clinician and statistician has significant experience in all the crucial aspects of the proposed research. Dr. Gordon and Dr. Kahn's experience centers on gait rehabilitation following spinal cord injury from neuromechanics and clinical perspectives respectively. Dr. Gordon's recent focus has been on the development of robotic devices to assess and train locomotor stability. Dr. Huang has significant experience investigating the use of rehabilitation robotic devices to foster motor learning and adaption. Environment: The proposed research project will be conducted in VA leased space within the Human Agility Laboratory located within the Northwestern University Department of Physical Therapy and Human Movement Sciences Department (PTHMS). The resources provided by PTHMS include dedicated research space and equipment, clinical examination areas, offices space and a machine shop. Primary recruitment of veterans with iSCI will be performed through the Spinal Cord Injury Service at Edward Hines Jr. VA Hospital. Proposed Research: Aim 1) To quantify the mechanisms used by individuals with iSCI to stabilize during maneuvers. We will quantify several biomechanical factors related to stability and maneuverability as people with iSCI perform a lane-change maneuver during over ground walking at preferred and maximum speeds. Outcomes from this research will provide the first biomechanical assessment of how individuals with iSCI change direction while walking. This information will be valuable for creating a theoretical framework for designing interventions that address the specific deficits and needs of this population. Aim 2) To develop robotic environments that promote and reinforce the use of active stabilization strategies during locomotor maneuvers. We will investigate two novel approaches to encourage practice of active mechanisms of stabilization during walking maneuvers by creating robotic assisted training environments that act to either stabilize or destabilize individuals as they walk. Altering the requirements of stabilization will encourage practice of different mechanisms of stability during maneuvers. Outcomes from this aim will provide a clear assessment of how robotic interventions can be manipulated to encourage practice of active mechanisms to stabilize maneuvers. This information will be crucial for designing targeted interventions to enhance mobility. Impact: We believe that identifying methods to enhance the ability of individuals with iSCI to utilize active mechanisms of stability will substantially improve dynamic balance. This is difficult because individuals with iSCI are highly dependent on passive mechanisms of stability whose presence interferes with attempts to train active mechanisms. Our approach to training dynamic balance is to use robotic environments to suppress passive mechanisms of stability so that individuals will become open to experience, practice and learn active mechanisms of stability. This approach is a radical departure from current practice and may have a substantial impact on the ability of individuals with iSCI to acquire dynamic balance capabilities.